In Ferris Bueller's Day Off (1986), during the parade, people seen dancing including the construction worker and the window washer had nothing to do with the film. They were simply dancing to the music being played, and John Hughes found it so humorous that he told the camera operators to record it.

Image from preview.redd.it and submitted by yesiamabrbafan
image showing In Ferris Bueller's Day Off (1986), during the parade, people seen dancing including the construction worker and the window washer had nothing to do with the film. They were simply dancing to the music being played, and John Hughes found it so humorous that he told the camera operators to record it.

HANDCRAFTEDD_ on June 4th, 2020 at 07:04 UTC »

Turns out, John was filming the whole time.

-Daws- on June 4th, 2020 at 07:05 UTC »

Do you know if they happened to have been credited?

whataTyphoon on June 4th, 2020 at 07:55 UTC »

I found the construction worker.